Oftentimes, to improve the performance of golf clubs the mass characteristics of a golf club head are altered to improve forgiveness and/or the length of the club is altered to increase head speed. However, the increased head weight and/or length in combination with conventional golf club shafts and grips often creates an undesirable feel during a swing of the golf club.
Golf club manufacturers have created the swing weight measurement to quantify the feel of rotating a golf club about a pivot point that is produced during a swing. Each of the components of a golf club has a mass and center of gravity location that is specific to its design and construction. The mass and location of the center of gravity of each component results in a net moment that can be calculated for any location along the club. Traditionally, swing weight has been quantified by determining the net moment applied by the components on a reference point designated at a location 14.0 inches from the butt end of the golf club.
The lengths of golf clubs through a set generally increase from the wedge-type clubs to wood-type clubs, which generally have lengths of 34.0-48.0 inches. Because of the lengths of the wood-type clubs and the location of the swing weight reference point, small changes in the weight of a club head and the length of the club have a dramatic impact on the swing weight of the assembled golf club.
Some manufacturers have done nothing to counter the effect of the increased length and/or heavier club heads and simply offer golf clubs having greater swing weight. As a result, the user is provided with a club that feels heavier through the swing, which is undesired by many players.
Others have made attempts to reduce the swing weight by adding weights at the grip end of the club and/or heavier grips to counteract the increased moment created by longer clubs and/or heavier club heads. For example, U.S. Pat. No. 4,690,407 to Reisner describes a weighted golf grip that includes a weight element fixed within the grip. The weighted grip is intended to weight the club behind the hands of the user to provide better control and tempo.
However, because the distance between the club head and the reference point is significantly greater than the distance between the reference point and the butt end of the golf club, any additional mass added on the club head end of the golf club must be counteracted by a much larger mass on the butt end of the golf club. As a result, a significant amount of weight must be added as a counterweight to balance even a small increase at the club head end and those weights add a significant amount of weight to the overall golf club weight. The increased overall weight also increases the difficulty in swinging the golf club.
Little attention has been given to the distribution of the existing weight in a golf club, especially the distribution of the weight of the shaft, which may also be used to alter the swing weight. Therefore, it is desirable to provide a golf club shaft that has a weight distribution that counteracts an increase in the swing weight of a golf club caused by an increase in length and/or club head weight.